Above-ground ground petroleum storage tanks are widely utilized. When a storage tank is overfilled or when fuel otherwise leaks or spills, such as from a rupture in the tank or associated piping, serious environmental damage may result. If the spill is left unchecked, fuel is apt to enter and pollute the ground water. Petroleum spills also waste valuable energy resources and can be extremely costly in terms of lost product, clean-up expense and storage facility downtime.
Government environmental regulations typically require secondary containment of petroleum that has spilled from an above-ground tank. Compliance with such regulations can be quite burdensome. For example, a regulation promulgated by the State of Florida has required that whenever a new above-ground storage tank is constructed in an existing dike field or tank farm facility, an approved secondary containment system must be installed for all existing tanks in the facility. The operator of a fuel storage tank farm is likely to incur costly installation expenses, delays and downtime to comply with this requirement.
Recently, the Florida Department of Environmental Protection has implemented a rule to ease the hardship created by the foregoing regulation. This rule permits the installation of an alternative secondary containment system limited to just the storage tank that is being constructed. If the requirements of the proposed rule are followed, costly and burdensome secondary containment does not have to be installed for all other existing tanks located at the facility.
In order to constitute an acceptable secondary containment system under the new Florida rule, the system must provide the following:                (a) continuous tank shell monitoring with approved probes, cables or electrical sensors;        (b) immediate electronic notification to the storage tank owner/operator of overfills and leaks from the tank shell;        (c) storm water management;        (d) an approved high-high level overfill alarm system with an annual test of operability;        (e) an impervious overfill retention system that will contain a volume of product that would be transferred at maximum flow rate for a period of five minutes by the pump(s) used for filling the tank; and        (f) an automatic system for shutting off the pump(s) used for filling the storage tank by an electronic signal from the continuous tank shell monitoring system; the system must be designed to operate in conjunction with the impervious overfill retention system and be capable of preventing any discharge of product being transferred during and after the time needed to shutoff the pump.        
There are no previously known secondary containment systems that meet all of the foregoing requirements. The system of the present invention is intended to provide an acceptable alternative secondary containment system as required by the Florida Department of Environmental Protection and has been approved for that purpose.